George,
Thanks for the info on formic use in Canada.

you wrote:
the full bottom entrance is left open throughout treatment.

* Right, it won't do to close them in four 6 weeks ! Also, we did a side by
side study of formic with regular and open screen bottoms. The open screen
did not *seem* to affect the effectiveness (not published yet, so don't ask).

you also wrote:
but I now I use Piston in the fall

* Huh? Never heard of that one !

pb

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